Computers at the Mackinac County Courthouse were infected by the Conficker virus, a program that infects computers and spreads itself to others connected on the same network, County Equalization Director James Fenlon told county commissioners at their meeting Thursday, August 13. The infection was detected August 5 by anti-virus programs installed on the county's computers.

The virus greatly slowed computers, Mr. Fenlon said, but caused no damage and was safely removed from the infected computers. The source is unknown, although infected USB drives are thought to be the cause. A worker may have used a county drive to perform work at home, which may have resulted in the drive contracting the worm accidentally, Mr. Fenlon said.

Some of the computers infected had not received Windows and virus definition updates. Workers are responsible for installing the updates, he said, and those who had not regularly updated their computers were infected. Employees were notified that installing the updates is important in preventing another infection.

Computers infected included a receipting computer in the treasurer's office, one in the clerk's office, a microfilm computer, and a public terminal.

All computers have been properly updated since the attack, Mr. Fenlon said.

No disciplinary action was discussed.